Okay, firstly, what is this anchor thing, is it literally an anchor lodged halfway through the SCP's mouth? I would add more description to that. Also how you introduced XXXX-1, you literally through it at us, there is also no mention of SCP-XXXX-1 in your special containment procedures. I would go into further detail regarding how XXXX-1 is attached to the original SCP.

And to be clear, this SCP has.

Metal skin of unknown origin

Titanium teeth, why titanium and why are the teeth known but the body isn't, and for that matter the anchor

a harpoon, is the harpoons compositional makeup known? what powers it if known?

tank treads…. sooooo does this SCP need to live in water or can it survive as indefinitely as it does in water on land as well.

you say it's diet is sea creatures, but then you mention "dirt and clothes" being expelled as waste does this mean it can survive on land based creatures as well?

I would personally do some rethinking on what your SCP actually does and doesn't do. There are also small grammatical errors throughout the page, you can probably find them in a proof read.

Skarfonic, if you're going to note grammar errors, please try to provide at least a few examples so the author knows what to look for, rather than being given no direction besides "proofread". Are these errors easy to find, like subject-verb disagreement, or harder to identify, like idiomatic phrasing issues? Don't assume that everything is obvious.